Edelbrock Exhaust System - Exhausting Efforts

Providing Potent Puff With Edelbrock's Header-Back System

Besides the obvious added performance benefits, the nice thing about the entire Edelbrock exhaust system is the emissions legality. Our '90 Chevy pickup features the integrated smog system, which Edelbrock has made accommodations for on the headers. (TES Headers are also available without the A.I.R. option, as well.)

Last month, as you'll recall, we gave an old workhorse Chevy fullsize truck new life with a Goodwrench replacement engine equipped with Edelbrock's Multi-Point Fuel Injection. The resulting performance improvements were pleasing, but knowing we could get more out of the energetic small-block with a little effort, we wasted no time in getting back to work.

Knowing that we were allowing more air into the engine, we figured, Why not make it possible for the spent gasses to exit just as efficiently? Edelbrock answered that question for us in the form of their TES (Tubular Exhaust System) Headers and Cat-Back System, which includes an RPM Series muffler. To make the package totally complete, we also selected a high-flow catalytic converter from CGS Motorsports.

The Header System improves the engine's ability to breathe, provides more efficient fuel economy, and most importantly, remains 50-state emissions-legal by retaining the use of all factory smog equipment (and the system will not void new vehicle warrantees). Extensive testing on behalf of Edelbrock has granted these particular headers an Executive Order Number, making them street legal on pollution-controlled vehicles. Manufactured from 409 stainless steel, the exhaust comes with a "shipping-protective" black paint that burns off at normal engine temps, so alternative coating should be arranged prior to installation, if desired.

The Cat-Back System, including the CGS cat, will work perfectly with the headers, providing less-restrictive flow than stock systems. Each mandrel-bent 16-gauge system is designed as a stock replacement, which means installation is a breeze. The RPM Series muffler (constructed from 409 stainless) features the patented Tru-Flow core design for improved sound and increased performance versus a typical baffle-type muffler, and is also street legal in all 50 states. And while the system is built to work with a stock catalytic converter, we chose to use CGS's higher-flow, weld-on cat for obvious reasons.

This phase of the upgrade started out at Barry White's Street Rod Repair, where Chad Vogele aptly handled the task of installing the Header System. One evening after work was all it took to get the headers bolted up, and the only hang-up we encountered was a pierced power steering pump (our fault). For the interim, the new connector pipe was tack-welded to the old catalytic converter until the remainder of the exhaust could be installed.

The next morning, we made an appointment at Apollo Muffler in Santa Ana, California, to finish up the job. With Apollo's talented staff, the wrap-up of our exhaust system took just under an hour to complete, including extra welding that isn't required (such as some of the slip joints). Once finished at the muffler shop, we got our first earful of the Edelbrock performance exhaust system, and were quite pleased. The real test, though, was yet to come.

The following week, a follow-up to our first dyno run was scheduled with Paul Trujillo at K&N Engineering in Riverside, California. We wanted to see exactly what horsepower and torque benefits the complete Edelbrock system provided compared to the earlier test results. When all was said and done, the truck produced a more than acceptable 173 hp at 4,400 rpm, and 238 ft-lb of torque at 3,100 rpm-quite a substantial improvement from what the small-block put out with just the Multi-Point Injection.

So, maybe this is not the high-horse Mouse motor that most readers dream about, but it sure gets this parts hauler around town (and across the highways) in fine fashion. Good throttle response, efficient fuel economy, and a healthy exhaust note to boot-the old workhorse is back and ready for action!

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Edelbrock Exhaust System - Exhausting Efforts

Besides the obvious added performance benefits, the nice thing about the entire Edelbrock exhaust system is the emissions legality. Our '90 Chevy pickup features the integrated smog system, which Edelbrock has made accommodations for on the headers. (TES Headers are also available without the A.I.R. option, as well.)

Options vary with different exhaust manifold applications, so we'll skip the removal of the stock exhaust. The installation of the TES Headers is straightforward, but you will want to remove the spark plugs to avoid breaking any when bolting the header in place.

The headers come supplied with flexible rubber hose (to connect with the stock tubing behind the block) for the A.I.R. system.

Spacers and hardware are also provided for the power steering pump bracket.

Due to the presence of various emissions components, the rightside header is a bit tougher to fit in place, but patience and persistence prevail. Notice the stovepipe Edelbrock has incorporated with the header tubing.

The crossover pipe should be assembled loosely before being installed, for obvious reasons.

Once everything fits in place and the collector flanges are flush with the header flanges, the wrenching can commence.

Edelbrock also provides an extension for the O2 sensor wire, shown here.

With the TES Header System installed, it was time to head over to Apollo Muffler for the remainder of the exhaust. The rear section of the Edelbrock Cat-Back System, including the RPM Series muffler, was bolted together prior to being hung.

While the exhaust system is designed for a clamp-on-style cat, the CGS Motorsports high-flow version was welded on to prevent any possible leaks.

With the cat all welded up, the back half of the exhaust was slipped in place. Edelbrock manufactures this particular system as a stock replacement, meaning all the factory mounting points are retained.

The inlet of the RPM Series muffler was heated up to allow the connector pipe to fit in nice and tight.

The cat-back setup sure looked good, but the true test would be once the engine was fired and the throttle depressed. Our initial test drive revealed that the complete Edelbrock system with the CGS cat sounded even better than it looked, and throttle response was crisper than ever.

All slip joints were completely MIG-welded up to ensure a "leak-less" exhaust system.

We still had to get some factual evidence of our exhausted efforts, so it was back to K&N for yet another dyno test. This time, we got hooked up with the company's new Xstream Air Flow Top for our Filtercharger air cleaner, to give us even more enhanced airflow.

Once Paul had completed this series of tests, it was determined that the Chevy now produced an improved 173 hp at 4,400 rpm and 238 ft-lbs of torque at 3,100 rpm, which has been quite noticeable during both city and highway driving. Our trusty workhorse is finally back in action-this time with a little attitude!

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